ISLA VISTA, Calif.—Before he set out on a deadly rampage through this seaside college town that ended with seven dead and 13 injured, suspected gunman Elliot Rodger calmly laid out his plans online.

The 22-year-old posted a YouTube video entitled "Elliot Rodger's Retribution," before he allegedly killed six people, at least three of them University of California Santa Barbara students. Looking directly into the...

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Elliot Rodger, accused of killing six people and injuring 13 others in a rampage in which he also died, published a 140-page, biographical manifesto. In it, he chronicles the evolution of his own hate and despair. WSJ's Jason Bellini reports.